Running Multiple XORP Instances In One Box

Jiaqing Du

Outline

• Introduction• XORP Overview• Running XORP• Configuring XORP• Experiment• Conclusion

Introduction

• XORP– eXtensible Open Router Platform– Why reinvent the wheel?

• Vision of authors– Why the Internet only just works

• Vision of MX– Control plane of Internet-in-a-lab

• Vision of others– Intel Research– Vyatta Inc.

XORP Overview

Control Plane

Data Plane

Running XORP (1/2)

• Virtual network interface– VLAN on Linux (802.1q kernel module)– Supported by XORP– Almost the same as physical interfaces

• Port conflicts– Finder: 127.0.0.1:19999– OSPF: raw socket– BGP: 179

Running XORP (2/2)

• OSPF traffic– Multicast packets– TTL = 1, dst = 224.0.0.5– setsockopt(), IP_MULTICAST_LOOP

OSPFv2XORP0

OSPFv2XORP1

Physical NIC

Virtual NIC

Configuring XORP

• Input– xml file describes network topology

• Intermediate– Ruby objects– AS, router, interface, link

• Output– XORP configuration files– startup and shutdown shell scripts

Experiment (1/2)

• Topology from VINI– 11 OSPF routers in a AS

• Another topology– Multiple ASes– Routes redistribution

Experiment (2/2)

AS0

AS1

AS2

Conclusion

• Deliverable– Slightly patched XORP-1.5– Configuration scripts

• Learned– How a router works– How routing protocols really work

Questions?